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2A651 CDC Vol 2
CDC Vol 2
Question | Answer |
---|---|
"An unbalanced force on a body produces or tends to produce acceleration in the direction of the force and that the acceleration, if any, is directly proportional to the force and inversely proportional to the mass of the body". This statement is | Newton's second law of motion |
Which type of duct would decrease the velocity and increase the pressure of a gas as it passes through? | Divergent |
What does fuel for an engine represent? | Potential energy |
Which section of a jet engine continually supplies air and maintains pressure? | Compressor |
Which section of a jet engine introduces and burns fuel? | Combustion |
Which section of a jet engine keeps the compressor rotating? | Turbine |
Through which section of a jet engine is energy expended into the atmosphere, resulting in thrust? | Exhaust |
How many British thermal units (BTUs) does the heat content per pound of kerosene produce? | 18,500 |
To measure barometric pressure, you would use a | barometer |
What is the sea-level atmospheric pressure in psi at "standard day" conditions? | 14.7 |
What effect does moisture content or humidity have on density of air in a jet engine? | More moisture, less dense |
What effect does the divergent design of a diffuser have on air pressure in a jet engine? | Increases pressure |
The air temperature of a jet engine gradually rises across the compressor to the diffuser outlet as a result of | Compression |
Where is the highest point of temperature reached in a jet engine? | Combustion section |
Which jet engine component meters fuel for combustion | Fuel control |
What is the required velocity for air and gases flowing through a jet engine? | Greater velocity exiting than entering |
What is the general flow of gases from the combustion chamber of the jet engine? | Parallel to the axis of the rotor shaft |
What directs the gases onto the first-stage turbine wheel blades in a jet engine? | Turbine stator |
When two or more turbine wheels are used in a jet engine, which component is placed directly in front of each turbine wheel? | Turbine stator (nozzle diaphragm) |
The operation of any gas turbine engine, regardless of type, requires the provisions made for three major functions. What are they? | Compression of air, expansion of air by burning fuel, and extraction of power from gases for driving the compressor and engine driven accessories |
The three major sections of all jet engines are compressor, combustion, and | Turbine |
Vane-type fuel pumps used in jet engines are similar to | Sliding-vane air compressors |
Which condition reduces the efficiency of a centrifugal compressor? | Pressure pulsations |
A constructional feature of the centrifugal compressor is that the impeller | Is forged as a single unit |
In a dual-spool compressor, revolutions per minute of the N2 compressor are determined by the | Fuel Control |
The jet engine compressor that is cheaper to manufacture is the | Centrifugal type, because of its fewer parts |
Which is a constructional feature of an axial-flow compressor casing? | Split horizontal centerline |
The percentage of combustion efficiency of a gas turbine is usually between | 95-100% |
Which facet of jet engine design helps prevent igniter plug fouling? | Directing air around the plug |
Carbon monoxide gas is poisonous and odorless, and has | No color |
What is the most chemically correct ratio for burning fuel in a combustion section of the jet engine? | 15:1 |
The excess airflow that is not burned in the combustion section of the jet engine is used to | Cool the burner surfaces |
The inner and outer surfaces of an annular-type combustion chamber are formed by | Interlocking stainless-steel bands |
Fuel that accumulates after a failed engine start is | Drained overboard by a drain system |
The parts on a can-annular combustion section must be removed in a specific order because of the | Combustion chamber crossover tubes |
What is the most common type of fuel nozzle system? | Pressure-atomizing |
Three types of turbine and vane assemblies used in jet engines are impulse, reaction, and | Reaction-impulse |
In the reaction type turbine, what in the design causes the rotor to turn? | The reduction in pressure and the increase in velocity of the exhaust gases occur in the passage between the rotor blades |
The "fir-tree" method of attaching turbine blades (buckets) to the turbine rotor disc is used most frequently? | Series of grooves of notches broached in the rim of the turbine rotor disc |
The exhaust duct connects the turbine outlet and the | Jet nozzle |
The design of an exhaust duct straightens the exhaust gases as it leaves the last stage of the turbine section to provide for | Larger total thrust in a more efficient manner |
The rear opening of the exhaust duct on the jet engine is referred to as the | Exhaust nozzle |
Some jet engines are timed/adjusted to their correct exhaust gas temperature by an alteration of what? | Exhaust nozzle area |
How many different types of loads can be imposed on a jet engine bearing? | 3 |
Before inspecting new jet engine bearings, you should | Remove the preservative coating |
Next to contamination and improper lubrication, what is the greatest enemy of antifriction bearings? | Improper removal |
The most commonly used bearing removal tools include | Arbor pressed and bearing pullers |
Which type of defect appears on bearings as a result of bearing parts striking together? | Nicks |
Which type of bearing defect results from inadequate lubrication? | Galling |
Excessive bearing wear can usually be detected by | Roughness of the metal |
Before you install separable bearings in a jet engine, you must make sure the | Bearings are a matched set |
To cause an accessory in a jet engine to operate at it's most optimum speed, design engineers must | Change the gear ratio |
On an F108 engine, the radial drive shaft connects the core engine to the | Accessory drive assembly |
Which F108 major engine module provides for mounting of the front of the engine to the airframe? | Fan major module |
Power to drive the accessory (AGB) on the F108 engine is transmitted from the | Accessory major module |
F108 structural rigidity is obtained with a short length and by having only two main structures that are called | Mainframes |
Primary airflow in the F108 engine is through all of the following components except the | Accessory gearbox |
Which type of load does the No. 2 bearing take up in the F108 engine? | Radial |
The F108 engine has an air duct through the inside diameter of the core compressor rotor that forms a flow path for | Pressurizing and cooling airflow |
On the F108 engine, the combustion chamber is which design type? | Annular |
On the F108 engine, the low-pressure turbine (LPT) shaft assembly connects the fan shaft with the | LPT rotor |
On the F108 engine, as gases flow through the convergent passageways of the low-pressure turbine (LPT) nozzle their pressure drops, and their axial velocity | Increases |
The F108 engine turbine frame is the engine rear main structural component, and it supports the | LPT rotor rear section |
On the F108 engine, what connects the IGB to the TGB bevel gears? | Radial drive shaft |
On the F108 engine, how is the TGB mounted to the fan case? | By a single clevis-and-link rod-mounting system arrangement |
On the TF34 jet engine, the fan forward shaft, bolted to the aft side of the double disc, is supported by | both the No. 1 thrust ball bearing and the No. 2 roller bearing. |
The single-stage fan rotor on the TF34 jet engine provides what percentages of the engines thrust? | 85% |
On the TF34 jet engine, which strut does the fan speed pickup protrude through to the number two bearing locknut? | 9 O' Clock |
The compressor inlet temperature sensor is mounted on the outer surface of the splitter nose at what "o'clock" position on the TF34 jet engine? | 9 O' Clock |
How many stages of compressor blades are in the TF34 engine? | 14 |
Why is the compressor stator case split horizontally? | To allow access to the compressor rotor |
What stages of compressor vanes are variable in the TF34 engine? | Stages 1-5 |
What type of combustion liner does the TF34 engine? | Annular |
On the TF34 jet engine, the first-stage nozzle consists of 24 cast segments with how many vanes in each segment? | 2 |
What is purpose of the low-pressure turbine transition assembly? | To funnel cool air from the HPT rotor to the larger diameter LPT rotor |
On the TF34 jet engine, which strut is used to port seventh stage compressor air into the C-sump area to pressurize the number six carbon seal? | 12 o' clock |
Which of these items does not belong to the TF34 engine accessories section? | Compressor stator |
In order to facilitate borescoping the engine, what is provided for rotating the high pressure rotor system and where is it located? | A gearbox cranking pad located between the lube and fuel pump pads |
Which one of these compressor section subsystems does not belong on the F117-PW-100 jet engine? | HPT group |
The HPC group on the F117-PW-100 jet engine consists of how many rotor stages and how many stages of stators surrounded by a two section titanium and steel case? | 12 rotors and 12 stators |
How many exit vanes make up the compressor exit stator assembly on the F117-PW-100 jet engine? | 72 |
The combustion chamber assembly provides the optimum environment for combustion and directs flow of | Hot gasses to the turbine nozzle |
Which of these turbine section subsystems does not belong on the F117-PW-100 jet engine? | LPC nozzle group |
Which one of these components is not an engine accessory component on the F117-PW-100 jet engine? | Radial drive shaft |
Which one of the listed components is not an aircraft accessory component on the F117-PW-100 jet engine? | LPT module |